<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Title</title>
</head>
<body>
<div id="app">
  <h2>总价格：{{totalPrice}}</h2>
</div>

<script src="../js/vue.js"></script>
<script>
  const app = new Vue({
    el: '#app',
    data: {
      books: [
        {id: 110, name: 'Unix编程艺术', price: 119},
        {id: 111, name: '代码大全', price: 105},
        {id: 112, name: '深入理解计算机原理', price: 98},
        {id: 113, name: '现代操作系统', price: 87}
      ]
    },
    computed: {
      totalPrice: function() {
        let result = 0;
        for(let i = 0; i < this.books.length; i++) {
          result += this.books[i].price;
        }
        return result;
      }
    }
  });
</script>
</body>
</html>